There are monitoring sites throughout California. There is a region in the Southeast of the state that is poorly covered by weather monitoring devices. There is a heavy concentration along the coastline, particularly in Los Angeles and San Francisco.
Section 4
In section 1, I already addressed the issue of implausible values for PM2.5 concentration (ones that were negative).
summary(epa0222$PM2.5)
Min. 1st Qu. Median Mean 3rd Qu. Max.
0.00 4.60 7.70 10.26 12.50 302.50
There do not appear to be any missing NA values.
Section 5
First, we will create summary statistics and exploratory plots for the state level.
table(epa0222$STATE)
California
73416
summary(epa0222$PM2.5)
Min. 1st Qu. Median Mean 3rd Qu. Max.
0.00 4.60 7.70 10.26 12.50 302.50
It appears that in California generally, the data is right-skewed, meaning most days have a lower mean PM2.5 level, but there are many outliers at higher levels. There is a daily mean of 10.2, though highest readings are above 300. This trend is particularly accentuated in the boxplot. The scatterplot shows that there are many higher individual mean days in 2022 as opposed to 2002.
Now, we will create summary statistics and exploratory plots for the county level.
table(epa0222$COUNTY)
Alameda Butte Calaveras Colusa Contra Costa
1989 1580 414 496 1097
Del Norte El Dorado Fresno Glenn Humboldt
562 436 3533 328 175
Imperial Inyo Kern Kings Lake
1743 2157 4113 804 122
Los Angeles Madera Marin Mariposa Mendocino
7003 360 573 868 821
Merced Modoc Mono Monterey Nevada
808 2 805 1221 1232
Orange Placer Plumas Riverside Sacramento
1350 1837 1451 5192 3360
San Benito San Bernardino San Diego San Francisco San Joaquin
594 3730 4476 546 1158
San Luis Obispo San Mateo Santa Barbara Santa Clara Santa Cruz
1598 449 1672 1651 752
Shasta Siskiyou Solano Sonoma Stanislaus
752 805 816 439 954
Sutter Tehama Trinity Tulare Ventura
829 347 489 1719 2691
Yolo
517
lac_data <-subset(epa0222, COUNTY =="Los Angeles")summary(lac_data$PM2.5)
Min. 1st Qu. Median Mean 3rd Qu. Max.
0.20 7.90 11.50 13.37 16.10 72.40
It appears that in Los Angeles county generally, the data is right-skewed, meaning most days have a lower mean PM2.5 level, but there are many outliers at higher levels. Mean PM2.5 level is 13.2 with highest numbers above 70. This trend is particularly accentuated in the boxplot. The scatterplot shows that the highest mean days of PM2.5 are in 2002 as opposed to 2020, which is different from the trends at the overall California level.
Now, we will create summary statistics and plots for the site in Los Angeles.
table(epa0222$'Site Name')
823
29 Palms
414
3425 N FIRST ST, FRESNO
499
Alpine
379
Alturas-Fourth St.
2
Anaheim
1123
Aqua Tibia Wilderness
168
Arroyo Grande CDF
359
Atascadero
350
Atascadero (original site)
116
Auburn-Atwood
350
Azusa
415
Bakersfield-Airport (Planz)
231
Bakersfield-California
2008
Bakersfield-Golden / M St
421
Banning Airport
365
Big Bear
450
Bishop Tribe EMO
354
Bliss SP
113
Brawley-220 Main Street
358
Brawley-401 Main St.
85
Burbank
122
Calexico-Ethel Street
613
Camp Pendleton
357
Campo Indian Reservation
362
Carmel Valley
343
Chester-222 First Ave
289
Chico-East Avenue
410
Chico-Manzanita Ave.
120
Chula Vista
218
Clovis-Villa
443
Colfax-City Hall
358
Colusa-Sunrise Blvd
454
Compton
723
Concord
739
Corcoran-Patterson
443
Cortina Indian Rancheria
42
Crescent City-Crescent Elk School
332
Crestline
178
Davis-UCD Campus
346
Death Valley NP - Park Village
115
Donovan
360
Echo Summit
2
El Cajon
416
El Cajon - Lexington Elementary School
491
El Centro-9th Street
452
El Rio-Rio Mesa School #2
469
Escondido
355
Eureka I Street
59
Folsom-Natoma St.
689
Fontana
298
Fremont - Chapel Way
105
Fresno - Garland
542
Fresno-Foundry
363
Fresno-Pacific
443
Gilroy
349
Glendora
361
Goleta
359
Grass Valley-Litton Building
406
Hanford-Irwin
361
Hollister
356
Hoover Wilderness
228
Huron
360
Indio
240
Jacobs
116
Joshua Tree NP - Black Rock
215
Kaiser Wilderness
195
Kearny Mesa
111
Keeler
641
King City 2
348
Lake Elsinore
360
Lake Tahoe Community College
111
Lakeport-Lakeport Blvd.
61
Lakeport-S. Main Street
61
Lancaster-Division Street
458
Laney College
360
Lassen Volcanic NP - Manzanita Lake Fire Station
210
Lava Beds National Monument
216
Lebec
489
Lebec-Peace Valley Road
93
Lebec-Peace Valley/Frazier Park Roads
106
Lee Vining
363
Lincoln-2885 Moore Road
357
Livermore
439
Lompoc H Street
358
Lone Pine Paiute-Shoshone Reservation
302
Long Beach (North)
411
Long Beach (South)
243
Long Beach-Route 710 Near Road
625
Los Angeles-North Main Street
1276
Lynwood
122
Madera-City
360
Mammoth
214
Manteca
340
Merced-Coffee
359
Merced-M St
449
Mesa2
358
Mira Loma (Van Buren)
778
Mission Viejo
227
Modesto-14th Street
598
Mojave
100
Mojave - CA 58 Business
355
Morongo Air Monitoring Station
370
North Hollywood (NOHO)
365
Oakland
365
Oakland West
359
Ojai - East Ojai Ave
360
Ontario Fire Station
111
Ontario-Route 60 Near Road
705
Pala Airpad
347
Palm Springs
239
Paradise - Theater
350
Pasadena
241
Pechanga
401
Pico Rivera #2
118
Pinnacles NP - Southwest of East Entrance Station
238
Piru - Pacific
475
Pleasanton - Owens Ct
361
Point Reyes NS Ranger Station
213
Porterville
356
Portola
552
Portola-161 Nevada Street
100
Quincy-N Church Street
510
Red Bluff-Walnut St. District Office
347
Redding - Buckeye
54
Redding - Health Department
429
Redding - Toyon
59
Redwood City
449
Redwood NP
230
Reseda
602
Ridgecrest-California Ave
104
Ridgecrest-Ward
355
Riverside (Magnolia)
115
Roseville-N Sunrise Ave
417
Rubidoux
1377
Sacramento Health Department-Stockton Blvd.
154
Sacramento-1309 T Street
826
Sacramento-Bercut Drive
359
Sacramento-Del Paso Manor
988
Salinas 3
530
San Andreas-Gold Strike Road
414
San Bernardino
235
San Diego - Kearny Villa Rd.
172
San Diego - Sherman Elementary School
437
San Diego -Rancho Carmel Drive
119
San Diego-12th Ave
352
San Francisco
546
San Jose
217
San Jose - 4th St.
141
San Jose - Jackson
586
San Jose - Knox Avenue
358
San Lorenzo Valley Middle School
345
San Luis Obispo-Marsh St.
52
San Pablo
358
San Rafael
360
San Rafael Wilderness
187
Santa Barbara
349
Santa Clarita
365
Santa Cruz
407
Santa Maria
60
Santa Rosa - 5th St
93
Sebastopol
346
Sequoia & Kings Canyon NPs - Ash Mountain
340
Sequoia NP-Ash Mountain
226
Signal Hill (LBSH)
289
Simi Valley-Cochran Street
873
SLO Roberto
363
Sloughhouse
344
South Lake Tahoe-Sandy Way
93
Stn.1 Big Pine Paiute site
325
Stockton - University Park
349
Stockton-Hazelton
124
Table Mountain Air Monitoring Site
339
Tahoe City-Fairway Drive
355
Temecula
365
Thousand Oaks
514
Torres Martinez Reservation
235
Tracy-Airport
345
TRAFFIC, RURAL PAVED ROAD
700
Tranquillity
349
Trinity
139
Truckee-Fire Station
826
Turlock
356
Ukiah-Library
470
Upland
365
Vallejo
816
Victorville-Park Avenue
944
Visalia-Church
404
Visalia-W. Ashland Avenue
393
Weaverville-Courthouse
350
White Mountain Research Center - Owens Valley Lab
420
Willits-Blosser Lane
351
Willows-Colusa Street
328
Woodland-Gibson Road
171
Yosemite NP - Turtleback Dome
340
Yosemite NP-Yosemite Village Vistor Center
528
Yreka
589
Yuba City
829
los_angeles_data <-subset(epa0222, `Site Name`=="Los Angeles-North Main Street")summary(los_angeles_data$PM2.5)
Min. 1st Qu. Median Mean 3rd Qu. Max.
2.40 8.90 12.40 14.56 17.20 66.30
It appears that in Los Angeles city, the data is right-skewed, meaning most days have a lower mean PM2.5 level, but there are many outliers at higher levels. Mean PM2.5 level is 14.6 with highest numbers above 60. This trend is particularly accentuated in the boxplot. The scatterplot shows that the highest mean days of PM2.5 are in 2002 as opposed to 2020, which is different from the trends at the overall California level.